It is estimated that one in every 10 infants born in the United States arrives prematurely, making it the greatest contributor to infant death among babies who were arrive before 32 weeks. Looking to reduce those numbers, researchers from the University of Adelaide in South Australia have been looking at a drug with the potential to prevent pre-term birth before symptoms even have a chance to appear.

Lead researcher Professor Sarah Robertson, the Director of the Robinson Research Institute, said that the drug Naloxone could be used much earlier in a pregnancy than previous treatments, potentially before any symptoms had developed.

“Most people when they think of labour, they just think of contractions and then the baby’s born,” she said.

“We’re targeting steps that happen much higher in that cascade of events, things that are occurring a lot earlier and a lot further upstream in that pathway.

“We’d be looking at which women were at risk in the second trimester of pregnancy and then commencing treatment soon thereafter.”

For this trial, the team focused on the use of Naloxone as a drug for long-term use, but Robertson said it would also be possible to use a higher dosage to delay a pregnancy in emergencies.

“There’s also a second use for women who come into a clinic, if they’re in sufficiently early stage labour, this drug will also have value as a kind of treatment.

Pre-term births occur due to inflammation responses in the mother’s body, caused by the immune system recognising the fetus as foreign and rejecting the pregnancy.